ByRobert I. Rotberg. Robert I. Rotberg is president of the World Peace Foundation in Cambridge, Mass.May 1, 1996

Elections and democracy go hand in hand, but not always. In Africa, where one-party dictatorships and military juntas once prevailed, democracy is gaining ascendancy. But only some democracies are completely democratic, and not every election consolidates a democratic transition.

During the last few weeks, three African countries have gone to the polls. In Sierra Leone, despite a raging civil war, citizens successfully cast ballots for a president, who duly took office from the leader of a military coup (who had himself ousted another military dictator). Ahmad Tejan Kabbah, a Muslim lawyer, defeated John Karefa-Smart, a well-known physician, in the final runoff.

In Benin, Nicephore Soglo, a democratic president, was voted out of office after five years in power. Those who went to the polls chose, instead, to reinstate Gen. Mathieu Kerekou, the once-Marxist military leader who ruled Benin repressively from 1972 to 1990. General Kerekou is from the north and Mr. Soglo from the south, so ethnic considerations were important. Also, Soglo was alleged to have abused the national trust by appointing relatives to key governmental positions. Accusations of nepotism and aloofness probably cost him a second term despite his reputation as a democrat.

These were standard popular exercises of choice appropriate to a recovering democracy like Sierra Leone or a fledgling democracy like Benin. Sierra Leonians had not enjoyed a free election since 1967. Since then, one-party rule or military dictatorship had reigned in the former British colony continuously, and rapaciously. Since 1990 shifting warlords and their gangs have terrorized much of the country. Democratically elected or not, it is unclear that President Tejan Kabbah can actually govern his recovering nation.

Benin, which holds the African record for coups since independence in 1960, made the transition from military to civilian rule in 1991. Now, democratically, the people of Benin are taking a step backward, even if President Kerekou faithfully upholds the Constitution and no longer intends to govern autocratically.

The third example is Zimbabwe, a democracy continuously since 1980, when the Zimbabwe African National Union (ZANU) led by President Robert Mugabe won the first post-colonial election. Zimbabwe - much larger and more prosperous than Benin and Sierra Leone - has a $5 billion gross domestic product and a sizeable number of white farmers.

Zimbabweans went to the polls in mid-March to reelect President Mugabe to another six-year term. He had two other septuagenarian opponents, both of whom were expected to win tiny percentages of the overall vote. But Mugabe and his government made it difficult for the Rev. Ndabaningi Sithole and the Rev. Abel Muzorewa to campaign, and the Constitution denied government campaign funds to any but Mugabe's party. Mugabe also used Air Force helicopters to tour the countryside and speak to potential voters.

The government controls the daily press, radio, and television. It recently pressured an independent weekly to discharge its editor, who had been critical of the president.

Mugabe's opponents obviously received less coverage. Moreover, Mr. Sithole had been under arrest for six months before the election. Last year, in a poll for parliament, the government ended up with 147 of the 150 seats. The full apparatus of the dominant party, and the weight of mainstream ethnic opinion, was behind Mugabe and the party in both elections.

In this year's presidential balloting, only 31 percent of the 4.9 million registered voters bothered to go to the polls. By election eve, both Sithole and Mr. Muzorewa had dropped out of the race. But the government went ahead with the contest anyway.

Muzorewa won almost 5 percent of the total votes. Sithole took 2 percent. Mugabe received the remainder. In the 1990 elections, 53 percent of the electorate voted, and Mugabe won 78 percent of the votes - against a challenger who was stronger than Sithole or Muzorewa.

Local political scientists at Zimbabwe's university said that this year's electoral exercise demonstrated that the country's democracy had no legitimacy. The head of the local Catholic Commission for Justice and Peace declared that democracy in Zimbabwe was an illusion. Mugabe, he and others declared, headed a one-party state masquerading as a democracy. The electoral farce revealed the shabbiness of the country's democratic pretensions.

Paradoxically, despite the quality of the recent election, and despite the absence of essentials like a free press, Zimbabwe most of the time appears to be more democratic than despotic. There is heavy-handed security, but most people never experience it. Indeed, the Zimbabwean government usually operates openly, even if its president brooks little opposition.

Leadership in developing countries makes an essential difference. After Mugabe, 71, leaves the presidency, Zimbabwe bids fair to become fully democratic in practice as well as in name. By then, Benin under President Kerekou should have consolidated its recently demonstrated democratic tendencies, and Sierra Leone, emerging from civil war, may have returned to its traditional democratic path under the leadership of President Tejan Kabbah.